perl return codes

[crokett]

does perl return any values after a script is finished? if the following is in a shell script, would it work?

if (perl somescript.pl)
then
do something
else
do some other thing
fi

thanks

[kmj]

Well, I know jack-doo about shell scripting and I've never deliberately returned any values from a perl script, but I threw the following two things together, and calling
prompt$ test.bash 0

causes it to say hello, while calling

prompt$ test.bash 1

causes it to say goodbye. The return values are the opposite of what I'd expect, but I'm sure that's because there's something that I don't know about bash.

test.bash:

#!/usr/bin/bash

if (./test.pl $1)
then
echo Hello!
else
echo Goodbye!
fi


test.pl

#!/usr/local/bin/perl


print "this is a test\n";
exit @ARGV[0];

[YaRness]

someone on a 'nix system just try


#!/usr/local/bin/perl
1

or "0", with the same type of bash script above, and see if it behaves like you'd think it would (prolly some benefit in ending a script with just "1" than "exit 1", though right now all i can think is that the exit command may just be unnecessary). i can't seem to figure out or remember which perl man page talks about this stuff. though reading up on the exit function in perlfunc (which also says to read up on the perlmod for a few more details) would definitely be a good idea.

[Stuka]

kmj-
The reason the results seem weird is due to old convention. Unlike C (and most programming languages I can think of), most OS's treat a program returning an exit code of 0 as normal, where a non-zero return code is abnormal.

[crokett]

i got back to a linux box today and wrote the following perl scripts:

test1.pl
perl test2.pl;

test2.pl
print "This is test2\n";

i wrote shell script:

if (perl test1.pl)
then
echo "success"
else
echo "Failure"
fi

after running the shell script with test2.pl there, the script echoed "succss". when i renamed test2, it echoed "failure". it looks like perl will return a false if it fails to execute a script.

[kmj]

Makes sense (a reply to both Stuka's and Crockett's posts. :) )